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AS2251
AS2301
Asphalt Screeds
AS2251 AS2301
Standard paving width 2.5 m 8' 2" 3.05 m 10'
Paving ranges:
hydraulically extendible 2.5 - 4.4 m 8' 2" - 14' 5" 3.05 - 5.49 m 10 - 18'
with bolt-on extensions 2.5 - 6.2 m 8' 2" - 20' 5" 3.05 - 7.32 m 10 - 24'
with cutoff shoes 1.9 m 6' 2" 2.44 m 8'
Optional Equipment Shown
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AS2251 / AS2301 Screed Features
Front-mounted, hydraulically driven extenders simplify paving
width changes and minimize handwork.
Screed extenders are supported by two
51 mm (2") diameter tubes that enhance
torsional resistance and rigidity.
Patented Pre-Strikeoff Shields allow the
proper amount of material to enter the
area in front of the main screed.
Width changes can be made from the
tractor, main screed or remote-mounted
control boxes, which are positioned at
the end of each extender.
Remote-mounted
extender control box
Main screed mat
thickness screw
Slope indicator
Height indicator
Thickness indicator
Main screed
control box
Extender
walkway
Main screed
burner
Main screed
walkway
Heavy-duty extender frame
members
Extender
burner
Pre-strikeoff
adjustment handles
Paving width
indicator
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Accurate width adjustment is measured
by a graduated scale that indicates
exactly how far the screed has extended
in inches and millimeters.
Extender height and slope can be
adjusted while the paver is operating.
Extenders are equipped with both
vibration and heat.
Extenders and vibrators are
hydraulically powered for reliable,
positive performance.
Remote-mounted
extender control box
Main screed
control box
Main screed mat
thickness screw
Height indicator
Trailing edge adjustment bolts
Patented Pre-strikeoff
Shields
Heavy-duty extender frame
members
Thickness indicator
Pre-strikeoff
adjustment handles
Slope indicator
Main screed
burner
Main screed
walkway
Paving width
indicator
Crown indicator
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Screed Plate Heating System
Highly efficient burner system provides fast, even screed plate heating.
Four diesel fuel burners, two on the
main screed and one on each extender,
provide fast screed plate heating.
Burners on main screed and extenders
are mounted on a replaceable, baffled
combustion chamber with flame
deflectors that direct heat to screed
plates, providing even heat distribution.
Full-length insulation over the
combustion chamber enhances heating
efficiency and minimizes heat transfer
to the screed frame.
Glow plug ignition is actuated from the
main screed control boxes.
Fuel nozzles incorporate check valves
that nearly eliminate visible smoke.
A built-in timer allows 15 minutes of
screed plate heating, preventing overheating of the plates.
Spring-loaded end gates create a
downward force that causes the gates to
follow the profile of the surface being
paved, assuring a good joint with the
adjacent mat.
False-wall design reduces mix contact
with the sliding portion of the gate,
providing easy gate adjustments.
Bolt-on design allows easy end gate
installation and removal.
Replaceable wear strip enhances end
gate service life.
Full-length end gate contains material,
providing an optimal longitudinal joint.
End Gates
Easy-to-adjust end gates ensure a good joint with the adjacent mat.
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Screed Plate Leveling
Save time with the trailing edge screed plate leveling system.
Screed plate leveling is quick and
convenient with the trailing edge
adjusting system, which eliminates
shims.
The trailing edge adjusting system
saves time when installing new screed
plates or when adjusting existing plates.
The trailing edge adjusting bolt system
hardware is plated to provide extra
corrosion resistance.
Screed Plates
Screed plates deliver a high-quality mat and a long service life.
Screed plates are constructed of
abrasion resistant alloy steel that resists
damage and provides an enhanced
service life. Quick screed replacement
improves maintenance time.
Curved nose bar design provides precompaction and enhances material flow
under screed.
Nose bar and screed plate replacement
are simplified with tapped holes and
studs.
Heavy-duty mounting platforms provide
rigid support for screed plates, which
simplifies leveling.
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Main screed control boxes are mounted
on each side of the screed and contain:
Extender in-out;
Feeder gain;
Burner ignition;
Horn; and
Feeders on-off.
Right side main screed control box also
contains the burner fuel pump switch
and vibrator on-off switch.
All other operational controls are
grouped near the main screed control
boxes, providing easy access and
enhancing operator efficiency.
Remote-mounted control boxes are
positioned on each extender and contain
a feeder control switch and extender inout control switch.
Extender width changes can also be
made by the tractor operator with a
switch on the operator’s console.
On-the-go slope and height adjustment
for extenders are made with easy-tooperate hand cranks, which are equipped
with positive-locking devices.
Screed Controls
Conveniently positioned extender and main screed control boxes
provide easy access to various screed functions.
Left side main screed
and extender controls
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Power Slope is standard on each
extender and can be sloped during
operation from +10% to -3% or +76 mm
to -25 mm. Indicators shows the percent
of slope.
Height adjustment allows each extender
to match the mat thickness being laid by
the main screed. Indicators show the
amount of adjustment in 6.4 mm (1/4")
increments.
Crown range is from +10% to -3% or
+133 mm to -38 mm. The amount of
crown is indicated on a scale near the
control.
Crown adjustment is made with an easyto-operate hand crank, which is
equipped with a positive-locking device.
Optional Power Controls for Crown and
Height include electric motor-driven
gearboxes that provide fingertip
operation of main screed crown and
extender height adjustments.
Diesel fuel burner on-off valves for the
main screed and extenders are positioned
below the main screed control boxes.
Right side main screed and
extender controls
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Serviceability
The AS2301 and AS2251 Screeds are easy and fast to service.
The screeds have been designed for
easy service and maintenance with
special emphasis given to component
access.
Hydraulic hoses and electrical wiring
harnesses are cleanly routed and
clamped to reduce wear and provide
easy service.
Diesel fuel burner lines are equipped
with a quick-disconnect coupling that
simplifies switching from the screed
plate heating system to the wash-down
system.
Remote-mounted fittings for vibrator
bearings provide simplified lubrication
access.
O-Ring Face Seal fittings and couplings
provide maximum protection against
hydraulic leaks.
Exposed hoses have nylon sleeve
protection to reduce abrasion.
Vibrator system hydraulic lines are
constructed of steel tubing, providing
durability and resistance to damage.
Integrity of the electrical system is
ensured with the use of high-quality
components.
The Caterpillar electrical standards,
developed to enhance reliability and
durability, feature soldered, molded,
numbered and color-coded wires.
Nylon-braided wrap protects the
electrical wires.
Electrical schematics detailing wire
numbers, wire colors and component
part numbers are located in the service
manual.
Pre-strikeoff shields allow the proper
amount of material to enter the area in
front of the main screed, which leads to
a smooth mat texture and helps prevent
segregation.
Two adjustment handles allow the
shield height to be fine tuned,
depending on the mix or operating
conditions.
When the thickness screws are used to
adjust mat depth, the pre-strikeoff
shields follow the leading edge of the
main screed, providing automatic
adjustment.
Patented Pre-Strikeoff Shields
A pair of pre-strikeoff shields are positioned at the front of the screed, making first contact
with the mix after it passes through the augers.
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Extender Slope
Each extender can be sloped during
operation from +10% to -3% or
+76 mm to -25 mm. Power slope is
standard. Indicators show the percent of
slope.
Crown
Crown adjustment is made with an easyto-operate hand crank, which is
equipped with a positive-locking device.
Crown range is from +10% to -3% or
+133 mm to -38 mm. Optional power
crown control can be added.
Extender Height
Height adjustment allows each extender
to match the mat thickness being placed
by the main screed. Adjustments are
made with easy-to-operate hand cranks,
which are equipped with positivelocking devices. Indicators show the
amount of adjustment in 6.4 mm (0.25")
increments. Optional power height
controls can be added.
Pre-Strikeoff Shields
A pair of patented pre-strikeoff shields
are positioned at the front of the screed.
The pre-strikeoff shields allow the
proper amount of material to enter the
area in front of the main screed, which
influences the head of material in front
of the main screed.
The pre-strikeoff shields follow the
leading edge of the main screed, when
the thickness screws are used to adjust
mat depth. These proportional changes
occur because the shields are attached to
the drop arms with mechanical linkages.
If manual adjustment of the shields is
desired, handles on the mechanical
linkages allow the height to be fine tuned.
Adjusting the handles only changes the
height of the pre-strikeoff shields. The
adjustment handles are located near the
main screed control boxes.
Hydraulic System
The extenders and vibrator systems are
hydraulically controlled with electricover-hydraulic components. The tractor
supplies hydraulic flow. Systems are
equipped with test ports for easy access
to sample pressures.
All hydraulic connections have O-ring
face seal (ORFS) fittings and couplings
to provide maximum protection against
hydraulic system leaks. High-pressure
Cat XT hoses provide an extended
service life.
Electrical System
The electrical system is 24-volts to
match the tractor. Integrity of the
electrical system on Cat machines is
ensured with the use of high-quality
components. The Caterpillar electrical
standards, developed to enhance
reliability and durability, feature
soldered, molded, numbered and colorcoded wires with nylon-braided wrap to
protect the electrical harness.
Screed Plates
Main and extender screed plate width,
measured front to back, is 457 mm
(18"). Main and extender screed plates
are constructed of 360 - 440 Brinnell
hardness alloy steel that helps resist
abrasion and extends wear life. Heavyduty mounting platforms provide rigid
support for screed plates, which
simplifies leveling.
Screed plate leveling is quick and
convenient with the trailing edge
adjusting system. Leveling is
accomplished with adjusting studs
mounted across the trailing edge of the
screed. The bolts thread into large nuts
welded onto the underside of the screed
frame. The trailing edge adjusting bolt
system hardware is plated to provide
extra corrosion resistance.
Extender Configuration
Two hydraulically driven extenders
infinitely vary screed width within the
paving range. The extenders are
positioned in front of the main screed.
The front-mounted extenders are
supported by two 51 mm (2") diameter
extendible tubes that provide torsional
resistance and rigidity.
Extender width changes can be made
from the tractor, main screed or remotemounted control boxes. The remotemounted control boxes are positioned at
the end of each extender.
Extenders are equipped with vibrators
and heaters that are separate from the
main screed. Vibrator motors and shafts
are hydraulically driven. Frequency and
amplitude are synchronized with main
screed vibrators.
Vibrator System
The main screed and extenders are
equipped with a vibrator system that
provides initial compaction. Vibrator
speed is adjustable from 0 to 50 Hz
(3,000 vpm).
Walkways
The main screed and each extender are
equipped with open-faced, slip-resistant
walkways. The walkways are 476 mm
(18.75") wide.
Thickness
Thickness control screws are located on
the outboard side of each control
console. The thickness screws
determines the paving depth. Four
thickness control screw thread
configurations are available.
End Gates
End gates are 1283 mm (50.5") long,
helping contain material and providing
an optimal longitudinal joint. End gates
are spring loaded, creating an adjustable
downward force that causes them to
follow the profile of the surface being
paved. The spring-loaded design also
creates a contained joint with the
adjacent mat.
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Customer Support
Cat dealer services help you operate longer with lower costs.
Your Cat Dealer offers a wide range of
services that can be set up under a
customer support agreement when
purchasing equipment. The dealer will
help customers choose a plan that can
cover everything from machine and
attachment selection to replacement, to
help get the best return on the machine
investment.
Selection. Make detailed comparisons of
the machines under consideration before
buying. How long do components last?
What is the cost of preventive
maintenance? What is the true cost of
lost production? Cat Dealers can give
precise answers to these questions.
Operation. Improving operating
techniques can boost one’s profits. Cat
Dealers have training videotapes,
literature and other ideas to help
increase productivity.
Purchase. Look past initial price.
Consider the financing options available
as well as day-to-day operating costs.
This is also the time to look at dealer
services that can be included in the cost
of the machine to yield lower equipment
owning and operating costs over the
long run.
Maintenance. More and more
equipment buyers are planning for
effective maintenance before buying
equipment. Choose from the dealer’s
wide range of maintenance services at
the time of purchase. Repair option
programs guarantee the cost of repairs
up front. Diagnostic programs such as
S•O•S oil analysis and Technical
Analysis help avoid unscheduled repairs.
Product support. Nearly all parts are
available at the Cat Dealer parts counter.
Cat Dealers utilize a worldwide
computer network to find in-stock parts
to minimize machine downtime.
Replacement. Repair, rebuild or
replace? Cat Dealers can help evaluate
the cost involved so the right choice is
made.
Screed Plate Heating
The screed plate heating system consists
of four diesel fuel burners, two on the
main screed and one on each extender.
The system provides fast and efficient
screed plate heating. A built-in timer
allows 15 minutes of screed plate
heating and then automatically shuts off,
preventing over-heating of the plates.
Most diesel vapors are eliminated by
controlling fuel pressure, directing air
flow and controlling fuel at the nozzles.
Controls
Controls are logically grouped providing
easy operation. Main screed control
consoles are mounted on each side of the
screed. They contain all electrically
actuated controls. All other operational
controls are grouped near the main
screed control consoles.
Remote-mounted control boxes are
mounted on the outboard surface of each
extender. They contain switches for
extender width and the feeder system.
Optional Equipment
Power Height allows each extender to
match the mat thickness being placed by
the main screed with switches in the
main screed control consoles. The
switches actuate electrical motors that
change extender height.
Power Crown allows the center of the
main screed to have crown applied to it
with a switch in the right main screed
control console. The switch actuates an
electrical motor that adjusts the crown.
Thickness Control Screw Configurations
are available to accommodate operator
preferences. The screed can be equipped
with one of four thickness control screw
thread configurations consisting of
clockwise standard thread,
counterclockwise standard thread,
clockwise Acme thread or
counterclockwise Acme thread.
Screed Extensions increase paving
width. Extensions are available in 305
mm (12") and 610 mm (24") widths.
Heat is by convection from the main
screed.
Cutoff Shoe Package allows the paving
width of a screed to be reduced up to
610mm (2'). The Cutoff Shoes are
available in either 305 mm (12") or 610
mm (24") widths. With either width, the
shoes can be varied in 76 mm (3")
increments.
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Dimensions
AS2251 Screed AS2301 Screed
A Length without End Gates (front to rear) 1478 mm (58") 1478 mm (58")
B Length with End Gates (front to rear) 1933 mm (76") 1933 mm (76")
C Width without End Gates 2.6 m (8' 9") 3.23 m (10' 7")
D Width with End Gates 2.8 m (9' 3") 3.38 m (11' 1")
E Height 2309 mm (91") 2309 mm (91")
E
A
C
D
B
Weights (approximate)
AS2251 Screed 3214 kg (7,070 lb)
AS2301 Screed 3355 kg (7,840 lb)
305 mm (1') Extension 73 kg (160 lb)
610 mm (2') Extension 152 kg (335 lb)
Paving Widths
AS2251 Screed AS2301 Screed
Standard paving width 2.5 m (8' 2") 3.05 m (10')
Paving ranges:
hydraulically extendible 2.5 - 4.27 m (8' 2" - 14' 5") 3.05 - 5.49 m (10 - 18')
with bolt-on extensions 2.5 - 6.10 m (8' 2" - 20' 5") 3.05 - 7.32 m (10 - 24')
with cutoff shoes 1.9 m (6' 2") 2.44 m (8')
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Caterpillar follows a policy of continual product improvement.
For this reason, some material and specifications could change without notice.
QEHQ9919 (4-02)
Replaces QEHQ9817
© 2002 Caterpillar
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